Legionnaires’ Disease: Are You At Risk?

HealthBy Janey DaviesOn June 8, 2012

With the number of confirmed cases of Legionnaires’ Disease in Edinburgh rising to 61 yesterday, experts believe they have finally stopped Scotland’s largest outbreak of the illness. Typically in a year you can expect to see approximately 30 to 40 new cases reported in the Scottish region, with around half of these contracted abroad. Health officials say that in all, nineteen cooling towers have been treated but it will be at least a week before the results can confirm which business was actually responsible for the initial outbreak. The Scottish minister said Legionnaires’ Disease was an “uncommon but serious form of pneumonia, caused by bacteria that are distributed widely in both natural and artificial water supplies. In most cases, the disease is caused by the inhalation of water containing the bacteria and common sources can be showers, air conditioning, cooling towers, or humidifiers.” The towers tested were at four different commercial sites, including the North British Distillery.

Legionnaires’ Disease is an illness, similar to pneumonia, which is caused by the legionella bacteria and can be potentially fatal. Anyone can get Legionnaires’ Disease, but some people are more suspectible if they have an impaired immune system, are over 45 years old, are smokers and heavy drinkers and suffer from any kind of chronic respiratory or kidney disease. The bacterium Legionella pneumophila live in low numbers in natural water sources such as rivers, lakes and reservoirs, and can also be found in water systems such as cooling towers, evaporative condensers and whirlpool spas. The bacteria can multiply if conditions are favourable which then increases the risk of Legionnaires’ Disease. This usually happens in purpose-built systems where the water is purposely maintained at a high enough temperature for the bacteria to grow. You catch the disease by inhaling small droplets of suspended water which contain the bacteria.

There are certain conditions which make the disease more likely to grow which include the water temperature being heated constantly between 20–45 °C, droplets of water being created which can then be breathed in, i.e an aerosol made by a cooling tower, or water outlets stored and/or re-circulated water, and some sort of food for the bacteria to feed on, i.e sludge, scale or fouling. You will find that although most cases of Legionnaires’ Disease are the result of infections caught in the UK, a small number of cases are contracted abroad. The symptoms of the disease are very similar to those of flu; you may experience high temperatures, fevers and chills, you could have a persistent cough, muscle aches and pains and a headache. In a severe case, this may progress to pneumonia, and the sufferer might exhibit signs of mental confusion. You cannot, however, catch Legionnaires’ Disease from another person who has already contracted it. It has to be inhaled from an infected water source. If you suspect that you may have the symptons of Legionnaires’ Disease you should visit your nearest A&E department.